Association between bacterial vaginosis and cervical intraepithelial neoplasia

The cervicovaginal metabolome in women with favorable induction cervix and those unfavorable for induction when delivering at term

Background

Cervical ripening is crucial for induction. However, its influencing factors, mechanistic understanding, and effective risk stratification are still challenging. Recent research suggested that microorganisms and their metabolites in vaginal spaces correlate to preterm birth. However, it remains unclear whether the cervicovaginal metabolome is related to the natural physiological process of cervical maturation.

Objective

We aimed to analyze the cervicovaginal metabolome in women with favorable induction cervix and those unfavorable for induction when delivering at term.

Study design

Cervicovaginal swabs were collected between 40 and 41 weeks gestation from the following 2 different groups of patients: Ripe group (n = 25) which was favorable for the induction cervix and Unripe group which was unfavorable for the induction cervix (n = 25). Samples were tested using untargeted metabolomics analysis and analyzed by a bioinformatics platform. The correlation analysis between the metabolome and the previously acquired microbiome was also performed.

Results

A total of 629 metabolites were identified in cervicovaginal fluid. The cervicovaginal metabolome was significantly different between the women with the ripe cervix and those with the unripe cervix, especially within each stratum of the same CST. Metabolites within the amino acid, carbohydrate, and dipeptide pathways may play a role in this distinction. Thirty-four metabolites were significantly upregulated, and the remaining fourteen were significantly downregulated in the Unripe group with an unripe cervix unfavorable for induction. Statistical modeling identified Arachidonic Acid and Nicotinate associated with the risk of cervical maturation disorder (AUC 0.87) in negative ion mode. A combination of Choline and d-Mannose identified a risk of cervical maturation disorder (AUC 0.80) in positive ion mode, improved by Lactobacillus relative abundance (AUC 0.89).

Conclusion

These data suggested that the cervicovaginal space was metabolically active during pregnancy and significantly altered among the women with the mature and immature cervix. Combining the genera-level phylotypes and metabolites could build better cervix maturity prediction models. By using cervicovaginal fluid samples, we demonstrated the potential of multi-data type integration for developing composite models toward understanding the contribution of the vaginal environment to the remodeling of cervix during term pregnancy.

Bacterial Vaginosis Decreases the Risk of Cervical Cytological Abnormalities

Genital tract infections, including vulvovaginal candidiasis and bacterial vaginosis, have emerged as potential modulators of persistent human papillomavirus (HPV) infections causing cervical cytologic abnormalities and cervical cancer. This study aimed to investigate whether vulvovaginal candidiasis or bacterial vaginosis had an additional effect on HPV infection and thus caused such abnormalities. ThinPrep cytologic tests were used to detect cytologic abnormalities, vulvovaginal candidiasis, and bacterial vaginosis in 14,679 women. Cytologic abnormalities included atypical squamous cells of undetermined significance, low-grade squamous intraepithelial lesions, high-grade squamous intraepithelial lesions, atypical squamous cells-cannot exclude HSIL, and squamous cell carcinoma. Logistic regression Model 1 (univariate regression) and Model 2 (multivariate logistic regression analysis adjusted for age combined with HPV infection) were used to analyze the association between bacterial vaginosis and cytologic abnormalities, or vulvovaginal candidiasis and cytologic abnormalities, alone or in the presence of HPV infection. Bacterial vaginosis infection rates were found to be significantly higher in the cytology-negative group among all participants and those with HPV infection (P = 0.003, P < 0.001, respectively). Analyses using Model 1 and Model 2 both pointed to bacterial vaginosis as a protective factor against cytologic abnormalities for all participants (OR = 0.36, 0.17, respectively, P < 0.05) and for HPV-infected participants (OR = 0.17, 0.16, respectively, P < 0.05). Neither vulvovaginal candidiasis nor vulvovaginal candidiasis + HPV was significantly associated with the incidence of cytologic abnormalities based on Model 1 (OR = 0.94, 0.71, respectively, P > 0.05) and Model 2 (OR = 0.91, 0.74, respectively, P > 0.05). Furthermore, neither vulvovaginal candidiasis nor bacterial vaginosis increased the incidence of cytologic abnormalities regardless of HPV infection status, while bacterial vaginosis might possibly prevent cytologic abnormalities in women coinfected by HPV.

PREVENTION RELEVANCE

Neither vulvovaginal candidiasis nor bacterial vaginosis was found to increase the incidence of cervical cytologic abnormalities with or without the presence of HPV. On the contrary, bacterial vaginosis may play a role in preventing cytologic abnormalities in women with HPV coinfection.

Common Microbial Genital Infections and Their Impact on the Innate Immune Response to HPV in Cervical Cells

The persistence of high-risk (HR) human papillomavirus (HPV) genotypes is a prerequisite of cervical cancer. It is not clear whether and how bacterial vaginosis (BV) and sexually transmitted infections (STIs) cause higher rates of persistent HPV infection. This study aimed to characterize mucosal innate immunity to HPV, comparing different conditions. Specifically, expression levels of genes coding for Toll-like receptors (TLR)7 and 9, several type III Interferon-related genes (IFNL1, 2, 3, their specific receptor subunit IFNLR1, and the IFN-stimulated gene ISG15). Chemokines CCL5 and CCL20 were measured in cervical cells positive, or not, for HPV, BV, and STIs. HPV DNA was detected in 51/120 (42.5%) enrolled women, two/third were HR-HPV genotypes. More than 50% of samples were BV- and/or STI-positive. HPV-positive women had BV, but not other STIs, more frequently than the HPV-negative. TLR9 and IFNL1 mRNAs were expressed in the LR, but much less in the HR HPV infection. Enhanced levels of TLR9, TLR7, IFNL2, and IFNLR1 were observed in HPV-positive women with BV and STI. TLR9-increased expression was associated with HPV persistence in previous studies; hence, bacterial coinfections may enhance this risk. Prospective measurements of type III IFNs and IFNLR1 are warranted to evaluate whether this response may act as a double-edged sword in infected epithelia.

Aerobic Vaginitis-Underestimated Risk Factor for Cervical Intraepithelial Neoplasia

The aim of this study is to analyse the association between vaginal microbiota and the histological finding of CIN. From July 2016 until June 2017, we included 110 consecutive patients with abnormal cervical cytology results referred for colposcopy to Riga East Clinical University Hospital Outpatient department in the study group. 118 women without cervical pathology were chosen as controls. Certified colposcopists performed interviews, gynaecological examinations and colposcopies for all participants. Material from the upper vaginal fornix was taken for pH measurement and wet-mount microscopy. Cervical biopsy samples were taken from all subjects in the study group and in case of a visual suspicion for CIN in the control group. Cervical pathology was more often associated with smoking (34.6% vs. 11.0%, p < 0.0001), low education level (47.2% vs. 25.5%, p = 0.001), increased vaginal pH (48.2% vs. 25.4%, p < 0.0001), abnormal vaginal microbiota (50% vs. 31.4%, p = 0.004) and moderate to severe aerobic vaginitis (msAV) (13.6% vs. 5.9%, p = 0.049) compared to controls. The most important independent risk factors associated with CIN2+ were smoking (OR 3.04 (95% CI 1.37–6.76), p = 0.006) and msAV (OR 3.18 (95% CI 1.13–8.93), p = 0.028). Bacterial vaginosis (BV) was found more often in CIN1 patients (8/31, 25.8%, p = 0.009) compared with healthy controls (8/118, 6.8%), or CIN2+ cases (8/79, 10.1%). In the current study msAV and smoking were the most significant factors in the development of CIN in HPV-infected women, especially high grade CIN. We suggest that AV changes are probably more important than the presence of BV in the pathogenesis of CIN and progression to cervix cancer and should not be ignored during the evaluation of the vaginal microbiota.

Revealing the Disturbed Vaginal Micobiota Caused by Cervical Cancer Using High-Throughput Sequencing Technology

Cervical cancer is the fourth most prevalent cancer type among all malignancies, so it is of great significance to find its actual pathogenesis mechanisms. In the present study, 90 women were enrolled, and high-throughput sequencing technology was firstly used to analyze the vaginal microbiota of healthy women (C group), cervical intraepithelial neoplasia patients (CIN group) and cervical cancer patients (CER group). Our results indicates that compared with C group, a higher HPV infection rate as well as increased Neutrophil ratio and tumor marker squamous cell carcinoma antigen (SCCA) were obtained, and a decrease in Lymphocyte ratio and Hemoglobin were also present. In addition, the cervical cancer showed a strong association with reduced probiotics Lactobacillus, increased pathogens Prevotella spp., Sneathia spp. and Pseudomonas spp. These results prove that the immunological changes generated by the cervical cancer and the vaginal microbiota can interact with each other. However, further study investigating the key bacteria for cervical cancer is still needed, which can be a clue for the diagnosis or treatment of cervical cancer.

Associations of sexually transmitted infections and bacterial vaginosis with abnormal cervical cytology: A cross-sectional survey with 9090 community women in China

Background

Although it is well acknowledged that persistent infection with high-risk human papillomavirus types in genital sites plays a crucial role in the development of squamous cell cervical carcinoma, there is no unanimous consensus on the association between non-HPV sexually transmitted infections and abnormal cervical cytology.

Methods

In the present study, we evaluated cervical cytology status, sexually transmitted infections and bacterial vaginosis status, and collected social-demographic information among recruited participants to explore the association of STIs and bacterial vaginosis with abnormal cervical cytology.

Results

9,090 women’s specimens were successfully tested, with a total of 8,733 (96.1%) women had normal cytology and 357 (3.9%) women exhibited abnormal cytology. The prevalence of HPV, Chlamydia trachomatis, Neisseria gonorrhoeae, and bacterial vaginosis was significantly higher in the ≥ASC-US group than the NILM group (P<0.05). Women with Neisseria gonorrhoeae infection (AOR = 5.30, 95% CIs = 1.30–21.51, P = 0.020) or bacterial vaginosis (AOR = 1.94, 95% CIs = 1.08–3.47, P = 0.026) exhibited an increased risk of abnormal cervical cytology after adjusted for carcinogenic HPV-positive status.

Conclusions

Our results demonstrated that Neisseria gonorrhoeae infection in genital sites and/or bacterial vaginosis may independently increase the risk for cervical cytology abnormalities after adjusted for carcinogenic HPV-positive status. Besides, these results improved our understanding of the etiology of abnormal cervical cytology and may be useful for the management of women with ASC-US cytology.

Bacterial vaginosis, representation of endocervical and/or metaplastic cells, and cytological abnormalities in different age groups: Association study

BACKGROUND

Studies have indicated that bacterial vaginosis (BV) might be a cofactor for the acquisition and persistence of high-risk papillomavirus, enabling the development of cytological abnormalities. The presence of endocervical and metaplastic cells makes the smear more adequate for the detection of these abnormalities once these cell types are representative of the transformation zone, a site of increased susceptibility to viral infection.

METHODS

The purpose of this study was to evaluate the patterns of vaginal microbiota, the representation of endocervical and/or metaplastic cells, and the detection of cytological abnormalities in cervical smears from women 15 to 64 years old. Results from satisfactory cytological smears performed in a laboratory school from the Federal University of Goiás were analyzed. The degree of association between the categorical variables was evaluated by the χ² test, Fisher's Exact test, and stratified analysis through the estimation of the prevalence ratio, with 95% confidence intervals and 5% statistical significance level (P < .05).

RESULTS

The global prevalence of BV and cytological abnormalities was 22.02% and 8.21%, respectively. BV and the representation of endocervical and/or metaplastic cells were independently associated with the detection of high-grade cytological abnormalities in the cervical smears of women between 25 and 64 years old.

CONCLUSIONS

BV and representation of endocervical and/or metaplastic cells were independently associated with the detection of high-grade cytological abnormalities reinforcing the importance of specimen adequacy and microbiota in the cervical microenvironment.

Reliability of conventional Papanicolaou smear in diagnosing bacterial vaginosis among women with clinical genital infection

OBJECTIVE

Bacterial vaginosis (BV) is a common reproductive tract infection (RTI) reported among Indian women. BV can influence the persistence of high-risk oncogenic human papillomavirus, a causative factor for cervical cancer. BV and cervical cancer are major public health issues in a developing country like India. It becomes important for a resource-constrained country like India with poor healthcare access to implement control measures to screen and treat RTI in an attempt to prevent the risk for cervical cancer. Papanicolaou (Pap) smear is an established screening tool for cervical cancer and the diagnosis of RTIs, forms a part of its evaluation. The present study explores the validity of conventional Pap smear in diagnosing BV.

METHODOLOGY

Pap smear and Gram stain smear were collected for 254 women with clinically evident cervicitis/cervicovaginitis (genital infection). Using the Nugent score on Gram stain as a gold standard, we determined the sensitivity and specificity of Pap smear to diagnose BV.

RESULTS

The overall prevalence of BV in the study population was 44% using the Nugent score. Pap smear showed sensitivity and specificity of 70.9%. (CI- 61.5% - 79.2%) and 56.8% (CI - 48.2%-65.2%), respectively. The positive predictive value of Pap smear to diagnose BV was 56.5% (CI - 47.8%-64.9%), and the negative predictive value was 71.2% (CI - 61.8%-79.4%).

CONCLUSION

In the present study, conventional Pap smear demonstrates good accuracy to detect BV. Pap testing for cervical cancer screening can additionally serve as an effective screening tool for diagnosing BV among women with genital infection in healthcare settings.

The vaginal metabolome and microbiota of cervical HPV-positive and HPV-negative women: a cross-sectional analysis

OBJECTIVE

Characterise the vaginal metabolome of cervical HPV-infected and uninfected women.

DESIGN

Cross-sectional.

SETTING

The Center for Health Behavior Research at the University of Maryland School of Public Health.

SAMPLE

Thirty-nine participants, 13 categorised as HPV-negative and 26 as HPV-positive (any genotype; HPV⁺ ), 14 of whom were positive with at least one high-risk HPV strain (hrHPV).

METHOD

Self-collected mid-vaginal swabs were profiled for bacterial composition by 16S rRNA gene amplicon sequencing, metabolites by both gas and liquid chromatography mass spectrometry, and 37 types of HPV DNA.

MAIN OUTCOME MEASURES

Metabolite abundances.

RESULTS

Vaginal microbiota clustered into Community State Type (CST) I (Lactobacillus crispatus-dominated), CST III (Lactobacillus iners-dominated), and CST IV (low-Lactobacillus, 'molecular-BV'). HPV⁺ women had higher biogenic amine and phospholipid concentrations compared with HPV^- women after adjustment for CST and cigarette smoking. Metabolomic profiles of HPV⁺ and HPV^- women differed in strata of CST. In CST III, there were higher concentrations of biogenic amines and glycogen-related metabolites in HPV⁺ women than in HPV^- women. In CST IV, there were lower concentrations of glutathione, glycogen, and phospholipid-related metabolites in HPV⁺ participants than in HPV^- participants. Across all CSTs, women with hrHPV strains had lower concentrations of amino acids, lipids, and peptides compared with women who had only low-risk HPV (lrHPV).

CONCLUSIONS

The vaginal metabolome of HPV⁺ women differed from HPV^- women in terms of several metabolites, including biogenic amines, glutathione, and lipid-related metabolites. If the temporal relation between increased levels of reduced glutathione and oxidised glutathione and HPV incidence/persistence is confirmed in future studies, anti-oxidant therapies may be considered as a non-surgical HPV control intervention.

TWEETABLE ABSTRACT

Metabolomics study: Vaginal microenvironment of HPV⁺ women may be informative for non-surgical interventions.

Association of Bacterial Vaginosis and Human Papilloma Virus Infection With Cervical Squamous Intraepithelial Lesions

OBJECTIVES

Human papillomavirus (HPV) is known to be associated with squamous intraepithelial lesions (SILs). However, there is limited and conflicting literature on the relationship between bacterial vaginosis (BV) and SIL. The aim of this study is to determine the prevalence of BV and evaluate the association between BV and SIL.

METHODS

A retrospective study was performed on 10,546 cases between 2012 and 2017. HPV results were available in 7,081 cases.

RESULTS

BV was present in 17.6% of cases. There was significant association between BV, positive HPV infection, and high-grade SIL. BV patients with negative HPV infection showed more squamous abnormalities than BV-negative HPV-negative patients.

CONCLUSIONS

We found there is a significant association between BV and SIL. BV is more common among patients with HPV infection and is independently associated with squamous abnormalities in cervical smears and surgical follow-up.

Long-term Lactobacillus rhamnosus BMX 54 application to restore a balanced vaginal ecosystem: a promising solution against HPV-infection

Background

Over recent years, a growing interest has developed in microbiota and in the concept of maintaining a special balance between Lactobacillus and other bacteria species in order to promote women’s well-being. The aim of our study was to confirm that vaginal Lactobacilli long-lasting implementation in women with HPV-infections and concomitant bacterial vaginosis or vaginitis might be able to help in solving the viral infection, by re-establishing the original eubiosis.

Methods

A total of 117 women affected by bacterial vaginosis or vaginitis with concomitant HPV-infections were enrolled at Department of Gynecological Obstetrics and Urological Sciences, La Sapienza University, Rome, Italy between February 2015 and March 2016. Women were randomized in two groups, standard treatment (metronidazole 500 mg twice a day for 7 days or fluconazole 150 mg orally once a day for 2 consecutive days) plus short-term (3 months) vaginal Lactobacillus implementation (group 1, short probiotics treatment protocol group, n = 60) versus the same standard treatment plus long-lasting (6 months) vaginal Lactobacillus rhamnosus BMX 54 administration (group 2, treatment group, n = 57).

Results

After a median follow up of 14 months (range 9–30 months) the chance to solve HPV-related cytological anomalies was twice higher in probiotic long-term users (group 2) versus short probiotics implementation group (group 1) (79.4% vs 37.5%, p = 0.041). Moreover, a total HPV-clearance was shown in 11.6% of short schedule probiotics implementation patients compared to a percentage of 31.2% in vaginal Lactobacilli long term users (p = 0.044), assessed as negative HPV-DNA test documented at the end of the study period.

Conclusions

The consistent percentage of clearance of PAP-smear abnormalities and HPV-clearance obtained in long-term treatment group has been interestingly high and encouraging. Obviously, larger and randomized studies are warranted to confirm these encouraging results, but we believe that eubiosis re-establishment is the key to tackle effectively even HPV-infection.

Trial registration

Retrospectively registered on PRS NCT03372395 (12/12/2017).

High Prevalence of Leptotrichia amnionii, Atopobium vaginae, Sneathia sanguinegens, and Factor 1 Microbes and Association of Spontaneous Abortion among Korean Women

Objective. The purpose of this study was to (i) determine the cervical microbial composition in different abortion samples and to (ii) investigate the correlation between spontaneous abortion and cervical microbes in Korean women. Methods. We collected cervical swabs from women who had never undergone abortion (N = 36), had spontaneous abortion (N = 23), and had undergone induced abortion (N = 88) and subjected those samples to 16S rRNA pyrosequencing. Further, factor analysis and correlation between cervical microbiota and spontaneous abortion were evaluated by logistic regression analysis. Results. In spontaneous abortion women, 16 S rRNA gene sequences showed significant increases in Atopobium vaginae, Megasphaera spp., Gardnerella vaginalis, Leptotrichia amnionii, and Sneathia sanguinegens compared to women in nonabortion group. In multivariate logistic regression analysis, A. vaginae (OD = 11.27; 95% = 1.57–81), L. amnionii (OD = 11.47; 95% = 1.22–107.94), S. sanguinegens (OD = 6.89; 95% = 1.07–44.33), and factor 1 microbes (OD = 16.4; 95% = 1.88–42.5) were strongly associated with spontaneous abortion. Conclusions. This study showed a high prevalence of L. amnionii, A. vaginae, S. sanguinegens, and factor 1 microbes in spontaneous abortion and association with spontaneous abortion in Korean women.

Bacterial Vaginosis and Cervical Intraepithelial Neoplasia: Is there an Association or is Co-Existence Incidental?

Objectives:

To determine associations, if any, of bacterial vaginosis with cervical pre-neoplastic lesions and evaluate any effects of sub-categorization of smears with bacterial vaginosis.

Methods:

All cervico-vaginal smears reported as positive for bacterial vaginosis over a five-year period were reviewed and sub-categorized into ’type I (dysbacteriosis)’ and ’type II (pure Gardenerella infection)’ smears by two cytopathologists (PS, SG). The proportion of smears with healthy flora and pre-neoplastic lesions was compared with those having bacterial vaginosis in conjunction with such changes. In addition, a comparison was also attempted between the frequencies of pre-neoplastic lesions with the two categories of bacterial vaginosis smears.

Results:

Bacterial vaginosis was diagnosed in 28.6% (7017 of the 24,565) of the 24,565 smears received in the Institute during the study period. Of these 7,017 smears with bacterial vaginosis, 53% (3717) were categorized as type I and 42.7% (3000) as type II by both cytopathologists. Pre-neoplastic lesions were detected in 10.2% of smears with bacterial vaginosis compared to 5.7% of those with healthy flora (P<0.0001). Of the sub-categories of bacterial vaginosis, the risk of detecting precancerous lesion was higher for type II smears (P<0.001).

Conclusion:

Sub-categorization of bacterial vaginosis, as performed in the Dutch coding system, may be worthwhile due to the strikingly different risk of associated preneoplasia.

The Effect of Lactobacillus crispatus and Lactobacillus rhamnosusCulture Supernatants on Expression of Autophagy Genes and HPV E6 and E7 Oncogenes in The HeLa Cell Line

OBJECTIVE

The aim of this study was to clarify the mechanism by which lactobacilli exert their cytotoxic effects on cervical cancer cells. In addition, we aimed to evalu- ate the effect of lactobacilli on the expression of human papilloma virus (HPV) onco- genes.

MATERIALS AND METHODS

In this experimental study, using quantitative real-time polymer- ase chain reaction (PCR), we analyzed the expression of CASP3 and three autophagy genes [ATG14, BECN1 and alpha 2 catalytic subunit of AMPK (PRKAA2)] along with HPV18 E6 and E7 genes in HeLa cells before and after treatment with Lactobacillus crispatus and Lactobacillus rhamnosus culture supernatants.

RESULTS

The expression of CASP3 and autophagy genes in HeLa cells was de- creased after treatment with lactobacilli culture supernatants. However, this de- crease was not significant for PRKAA2 when compared with controls. In addition, expression of HPV E6 was significantly decreased after treatment with lactobacilli culture supernatants.

CONCLUSION

Lactobacilli culture supernatants can decrease expression of ATG14 and BECN1 as well as the HPV E6 oncogene. It has been demonstrated that the main changes occurring during cervical carcinogenesis in cell machinery can be reversed by suppression of HPV oncogenes. Therefore, downregulation of HPV E6 by lacto- bacilli may have therapeutic potential for cervical cancer. As the role of autophagy in cancer is complicated, further work is required to clarify the link between downregula- tion of autophagy genes and antiproliferative effects exerted by lactobacilli.

Association between Obesity and Cervical Microflora Dominated by Lactobacillus iners in Korean Women

Lactobacillus spp. are associated with the maintenance of reproductive health, but obesity reduces fertility and is a risk factor for obstetric and neonatal complications. We assessed the association between obesity and the cervical Lactobacillus composition, which has not been examined previously. Pyrosequencing was performed using cervical swabs collected from 76 normal participants with negative results for cervical intraepithelial neoplasia (CIN) and 57 participants with CIN, based on histological examinations. Cluster analysis of nine Lactobacillus spp. was performed, and five cluster types were identified. The association between obesity and the Lactobacillus community was assessed by logistic regression analysis after adjustment for confounding factors. The proportion of Lactobacillus iners increased and that of Lactobacillus crispatus decreased according to body mass index (BMI) categories, i.e., underweight (BMI of <18.5 kg m(-2)), normal weight (BMI of 18.5 to 22.9 kg m(-2)), overweight (BMI of 23.0 to 24.9 kg m(-2)), and obese (BMI of ≥25 kg m(-2)). The L. iners-dominant type had a significant association with obesity (odds ratio [OR], 7.55 [95% confidence interval [CI], 1.18 to 48.2]), compared to the L. crispatus-dominant type. The group with high values for the ratio obtained by dividing the relative abundance of L. iners by that of L. crispatus had a significant association with obesity (OR, 6.54 [95% CI, 1.22 to 35.1]), compared to the low-ratio group. Associations between obesity and the L. iners/L. crispatus ratio were observed among young women (OR, 6.26 [95% CI, 1.15 to 33.9]) but not older women and in the normal group (OR, 6.97 [95% CI, 1.20 to 70.4]) but not the CIN group. Obesity was associated with cervical microflora dominated by L. iners in reproductive-age women without dysplasia.

The association of uterine cervical microbiota with an increased risk for cervical intraepithelial neoplasia in Korea

Recent studies have suggested potential roles of the microbiome in cervicovaginal diseases. However, there has been no report on the cervical microbiome in cervical intraepithelial neoplasia (CIN). We aimed to identify the cervical microbiota of Korean women and assess the association between the cervical microbiota and CIN, and to determine the combined effect of the microbiota and human papillomavirus (HPV) on the risk of CIN. The cervical microbiota of 70 women with CIN and 50 control women was analysed using pyrosequencing based on the 16S rRNA gene. The associations between specific microbial patterns or abundance of specific microbiota and CIN risk were assessed using multivariate logistic regression, and the relative excess risk due to interaction (RERI) and the synergy index (S) were calculated. The phyla Firmicutes, Actinobacteria, Bacteroidetes, Proteobacteria, Tenericutes, Fusobacteria and TM7 were predominant in the microbiota and four distinct community types were observed in all women. A high score of the pattern characterized by predominance of Atopobium vaginae, Gardnerella vaginalis and Lactobacillus iners with a minority of Lactobacillus crispatus had a higher CIN risk (OR 5.80, 95% CI 1.73-19.4) and abundance of A. vaginae had a higher CIN risk (OR 6.63, 95% CI 1.61-27.2). The synergistic effect of a high score of this microbial pattern and oncogenic HPV was observed (OR 34.1, 95% CI 4.95-284.5; RERI/S, 15.9/1.93). A predominance of A. vaginae, G. vaginalis and L. iners with a concomitant paucity of L. crispatus in the cervical microbiota was associated with CIN risk, suggesting that bacterial dysbiosis and its combination with oncogenic HPV may be a risk factor for cervical neoplasia.

High incidence of oncogenic HPV genotypes found in women from Southern Brazil

Oncogenic HPV genotypes are strongly associated with premalignant and malignant cervical lesion. The purpose was to determine human papillomavirus (HPV) prevalence and genotypes, and to estimate cervical cancer risk factor associations. Cervical samples were obtained from 251 women seeking gynecological care at the Pelotas School of Medicine Clinic. This is a cross-sectional study. HPV-DNA was amplified by nested-PCR using MY09/11 and GP5/6 primers, and the sequencing was used for genotyping. Sociodemographic and behavioral risk factors were obtained by closed questionnaire, and its relationship to HPV infection prevalence were analyzed. Statistical analyses were performed using SPSS 16.0 software, and differences were considered significant at p < 0.05. As results, the prevalence of HPV infection was 29.9%. The most frequent genotype was HPV-16 (41.3%), followed by HPV-18 (17.3%), and HPV-33 (9.3%). Others nine HPV genotypes were also found. On this population, prevalence of oncogenic HPV genotypes was high, but does not seem to confer relationship with the risk factors investigated. Future investigations in larger populations are necessary, for the proposition of more appropriated monitoring strategies and treatment according to the Brazilian health service reality, as well as patients.

Evaluation of microbial enzymes in normal and abnormal cervicovaginal fluids of cervical dysplasia: a case control study

The aim of the present study was to evaluate the role of microbial enzymes in normal and abnormal cervicovaginal fluids of cervical dysplasia. The cervicovaginal infections were evaluated through the estimation of microbial enzymes in patients with and without abnormal cervical cytology like bacterial and fungal infections. The patients were categorized based on infection caused by organism and stages of dysplasia. The pH, Whiff test, and Pap smear tests were conducted for normal and abnormal cervical swabs based on standard protocols. Microbial enzymes include mucinase, sialidases, and proteases of the cervical swabs and are estimated according to standard methods. The results of abnormal cervical cytological smears showed increased pH and the presence of amines with different levels of Pap smear test. Increased levels of microbial enzymes were observed in patients with abnormal cytology than normal cytology. Three microbial enzymes mucinase, sialidase, and protease were significantly (P < 0.01) more elevated in patients with bacterial infections (8.97 ± 0.64, 10.39 ± 0.28, 8.12 ± 0.64) than without dysplasia (2.02 ± 0.8, 1.98 ± 0.3, 1.96 ± 0.8). The results reinforce that the microbial infection seems to be more prone to cervical dysplasia and may act as risk-factor for the development of cervical cancer along with HPV infection.

Comparison of the vaginal microbiota diversity of women with and without human papillomavirus infection: a cross-sectional study

Background

The female genital tract is an important bacterial habitat of the human body, and vaginal microbiota plays a crucial role in vaginal health. The alteration of vaginal microbiota affects millions of women annually, and is associated with numerous adverse health outcomes, including human papillomavirus (HPV) infection. However, previous studies have primarily focused on the association between bacterial vaginosis and HPV infection. Little is known about the composition of vaginal microbial communities involved in HPV acquisition. The present study was performed to investigate whether HPV infection was associated with the diversity and composition of vaginal microbiota.

Methods

A total of 70 healthy women (32 HPV-negative and 38 HPV-positive) with normal cervical cytology were enrolled in this study. Culture-independent polymerase chain reaction-denaturing gradient gel electrophoresis was used to measure the diversity and composition of vaginal microbiota of all subjects.

Results

We found significantly greater biological diversity in the vaginal microbiota of HPV-positive women (p < 0.001). Lactobacillus, including L. gallinarum, L. iners and L. gasseri, was the predominant genus and was detected in all women. No significant difference between HPV-positive and HPV-negative women was found for the frequency of detection of L. gallinarum (p = 0.775) or L. iners (p = 0.717), but L. gasseri was found at a significantly higher frequency in HPV-positive women (p = 0.005). Gardnerella vaginalis was also found at a significantly higher frequency in HPV-positive women (p = 0.031). Dendrograms revealed that vaginal microbiota from the two groups had different profiles.

Conclusions

Our study is the first systematic evaluation of an association between vaginal microbiota and HPV infection, and we have demonstrated that compared with HPV-negative women, the bacterial diversity of HPV-positive women is more complex and the composition of vaginal microbiota is different.

Normal and tumour cervical cells respond differently to vaginal lactobacilli, independent of pH and lactate

Cervical cancer is a human papilloma virus (HPV)-related cancer, but most HPV infections are transient or intermittent and resolve spontaneously. Thus, other factors, such as cervical microflora, which are dominated by lactobacilli, must be involved in invasive cervical carcinoma development after HPV infection. Previous studies have demonstrated that lactobacilli have antitumour effects, and it is possible that vaginal lactobacilli prevent cervical cancer. Here we examined the proliferative and apoptotic responses of normal and tumour cervical cells to common vaginal lactobacilli components by investigating human normal fibroblast-like cervical (normal cervical) and HeLa (cervical tumour) cell responses to Lactobacillus gasseri and Lactobacillus crispatus. The effects of different lactobacilli components, such as culture supernatants, cytoplasmic extracts, cell-wall extracts and live cells, were determined by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, trypan blue staining, lactate dehydrogenase assay and colorimetric caspase-3 activity assay. Changes in caspase-3 and human chorionic gonadotropin β (hCGβ) expression were analysed by quantitative RT-PCR. Tumour cell growth inhibition by culture supernatants was higher than that by pH- and lactate-adjusted controls. However, the effects of the supernatants on normal cells were similar to those of lactate-adjusted controls. Apoptosis was inhibited by supernatants, which was consistent with higher hCGβ expression since hCG inhibits apoptosis. Our study demonstrated that common vaginal lactobacilli exert cytotoxic effects on cervical tumour cells, but not on normal cells, and that this cytotoxicity is independent of pH and lactate. Our results encourage further studies on the interaction between lactobacilli and cervical cells, and administration of common vaginal lactobacilli as probiotics.

Association between bacterial vaginosis and cervical intraepithelial neoplasia: systematic review and meta-analysis

OBJECTIVE

Bacterial vaginosis (BV), the most common vaginal disorder among women of reproductive age, has been suggested as co-factor in the development of cervical cancer. Previous studies examining the relationship between BV and cervical intra-epithelial neoplasia (CIN) provided inconsistent and conflicting results. The aim of this study is to clarify the association between these two conditions.

METHODS

A systematic review and meta-analysis were conducted to summarize published literature on the association between BV and cervical pre-cancerous lesions. An extensive search of electronic databases Medline (Pubmed) and Web of Science was performed. The key words 'bacterial vaginosis' and 'bacterial infections and vaginitis' were used in combination with 'cervical intraepithelial neoplasia', 'squamous intraepithelial lesions', 'cervical lesions', 'cervical dysplasia', and 'cervical screening'. Eligible studies required a clear description of diagnostic methods used for detecting both BV and cervical pre-cancerous lesions. Publications were included if they either reported odds ratios (OR) and corresponding 95% confidence intervals (CI) representing the magnitude of association between these two conditions, or presented data that allowed calculation of the OR.

RESULTS

Out of 329 articles, 17 cross-sectional and 2 incidence studies were selected. In addition, two studies conducted in The Netherlands, using the national KOPAC system, were retained. After testing for heterogeneity and publication bias, meta-analysis and meta-regression were performed, using a random effects model. Although heterogeneity among studies was high (χ(2) = 164.7, p<0.01, I(2) = 88.5), a positive association between BV and cervical pre-cancerous lesions was found, with an overall estimated odds ratio of 1.51 (95% CI, 1.24-1.83). Meta-regression analysis could not detect a significant difference between studies based on BV diagnosis, CIN diagnosis or study population.

CONCLUSIONS

Although most studies were cross-sectional and heterogeneity was high, this meta-analysis confirms a connection between BV and CIN.

The role of genital pathogens in morbidity following diathermy loop excision of the transformation zone of the uterine cervix

OBJECTIVE

To evaluate the role of genital pathogens in postoperative morbidity following diathermy loop excision of the transformation zone (LETZ) of the uterine cervix.

METHODS

Patients with cervical intraepithelial neoplasia (CIN) who underwent diathermy LETZ were included in a prospective study. Cervical swabs for genital pathogens were collected before the diathermy procedure. After surgery, women were followed-up regarding the occurrence and severity of postoperative pain, bleeding, and discharge.

RESULTS

Genital pathogens were present in 463 of 788 (58.8%) cases. The most frequently isolated groups of microorganisms were group B β-hemolytic Streptococcus, α-hemolytic Streptococcus, Enterococcus species, and coliforms. In patients with genital pathogens, postoperative pain was present in 298 (37.8%), discharge in 262 (33.2%), and bleeding in 236 (29.9%) cases. In patients without genital pathogens, 199 (25.3%) experienced pain, 181 (23.0%) discharge, and 143 (18.1%) bleeding. The differences between the 2 groups were not statistically significant (χ(2) for pain=0.675; χ(2) for discharge=0.031; χ(2) for bleeding=3.444; P>0.05).

CONCLUSION

Genital pathogens are very common among patients with CIN and do not affect the occurrence or severity of pain, discharge, or postoperative bleeding after diathermy LETZ.

Bacterial vaginosis and the natural history of human papillomavirus

OBJECTIVE

To evaluate associations between common vaginal infections and human papillomavirus (HPV).

STUDY DESIGN

Data from up to 15 visits on 756 HIV-infected women and 380 high-risk HIV-uninfected women enrolled in the HIV Epidemiology Research Study (HERS) were evaluated for associations of bacterial vaginosis, trichomoniasis, and vaginal Candida colonization with prevalent HPV, incident HPV, and clearance of HPV in multivariate analysis.

RESULTS

Bacterial vaginosis (BV) was associated with increased odds for prevalent (aOR = 1.14, 95% CI: 1.04, 1.26) and incident (aOR = 1.24, 95% CI: 1.04, 1.47) HPV and with delayed clearance of infection (aHR = 0.84, 95% CI: 0.72, 0.97). Whereas BV at the preceding or current visit was associated with incident HPV, in an alternate model for the outcome of incident BV, HPV at the current, but not preceding, visit was associated with incident BV.

CONCLUSION

These findings underscore the importance of prevention and successful treatment of bacterial vaginosis.

The Strong Protective Effect of Circumcision against Cancer of the Penis

Male circumcision protects against cancer of the penis, the invasive form of which is a devastating disease confined almost exclusively to uncircumcised men. Major etiological factors are phimosis, balanitis, and high-risk types of human papillomavirus (HPV), which are more prevalent in the glans penis and coronal sulcus covered by the foreskin, as well as on the penile shaft, of uncircumcised men. Circumcised men clear HPV infections more quickly. Phimosis (a constricted foreskin opening impeding the passage of urine) is confined to uncircumcised men, in whom balanitis (affecting 10%) is more common than in circumcised men. Each is strongly associated with risk of penile cancer. These findings have led to calls for promotion of male circumcision, especially in infancy, to help reduce the global burden of penile cancer. Even more relevant globally is protection from cervical cancer, which is 10-times more common, being much higher in women with uncircumcised male partners. Male circumcision also provides indirect protection against various other infections in women, along with direct protection for men from a number of genital tract infections, including HIV. Given that adverse consequences of medical male circumcision, especially when performed in infancy, are rare, this simple prophylactic procedure should be promoted.

Bacterial vaginosis is associated with uterine cervical human papillomavirus infection: a meta-analysis

Background

Bacterial vaginosis (BV), an alteration of vaginal flora involving a decrease in Lactobacilli and predominance of anaerobic bacteria, is among the most common cause of vaginal complaints for women of childbearing age. It is well known that BV has an influence in acquisition of certain genital infections. However, association between BV and cervical human papillomavirus (HPV) infection has been inconsistent among studies. The objective of this meta-analysis of published studies is to clarify and summarize published literature on the extent to which BV is associated with cervical HPV infection.

Methods

Medline and Web of Science were systematically searched for eligible publications until December 2009. Articles were selected based on inclusion and exclusion criteria. After testing heterogeneity of studies, meta-analysis was performed using random effect model.

Results

Twelve eligible studies were selected to review the association between BV and HPV, including a total of 6,372 women. The pooled prevalence of BV was 32%. The overall estimated odds ratio (OR) showed a positive association between BV and cervical HPV infection (OR, 1.43; 95% confidence interval, 1.11-1.84).

Conclusion

This meta-analysis of available literature resulted in a positive association between BV and uterine cervical HPV infection.

Factors affecting transmission of mucosal human papillomavirus

Human papillomavirus (HPV) is the most common sexually transmitted infection. The effect of HPV on public health is especially related to the burden of anogenital cancers, most notably cervical cancer. Determinants of exposure to HPV are similar to those for most sexually transmitted infections, but determinants of susceptibility and infectivity are much less well established. Gaps exist in understanding of interactions between HPV, HIV, and other sexually transmitted infections. The roles of mucosal immunology, human microbiota at mucosal surfaces, host genetic factors and hormonal concentrations on HPV susceptibility and infectivity are poorly understood, as are the level of effectiveness of some primary or secondary preventive measures other than HPV vaccination (such as condoms, male circumcision, and combination antiretroviral therapy for HIV). Prospective couples studies, studies focusing on mucosal immunology, and in-vitro raft culture studies mimicking HPV infection might increase understanding of the dynamics of HPV transmission.